1. Field of the Invention
The present invention relates to an image pickup apparatus.
2. Description of the Related Art
Image pickup apparatuses having an image pickup device, such as a CCD image sensor or a CMOS image sensor, have been proposed.
These image pickup apparatuses are used as digital still cameras or video cameras, car-mounted cameras mounted outside a car body or inside a cabin, as outside surveillance cameras.
Most image pickup apparatuses used as car-mounted cameras or surveillance cameras include a housing serving as an outer casing, a barrel incorporated in the housing, a lens incorporated in the barrel so as to constitute an imaging optical system, and an image pickup device provided in the housing so as to capture a subject image guided by the imaging optical system, for example, as disclosed in Japanese Unexamined Patent Application Publication No. 2005-266276.
FIG. 4 shows an image pickup apparatus 10′ disclosed in the above-described publication. The image pickup apparatus 10′ includes a housing 50 serving as an outer casing, a barrel 52 incorporated in the housing 50, a lens 54 incorporated in the barrel 52 so as to constitute an imaging optical system, an image pickup device 56 provided in the housing 50 so as to capture a subject image guided by the imaging optical system, and a lens cover 58 screwed on the front of the barrel 52 so as to fix the lens 54 to the barrel 52.
The image pickup device 56 is mounted on a printed wiring board 64 that is screwed to the housing 50.
In order to adjust the distance between the lens 54 and the image pickup device 56 during assembly of the image pickup apparatus 10′, an external thread 5202 provided on the barrel 52 is coupled to an internal thread 5002 provided on the housing 50 by screwing.
Further, in order to ensure resistance to water, a first O-ring 60 is provided between the lens 54 and the barrel 52, and a second O-ring 62 is provided between the barrel 52 and the housing 50.
In this image pickup apparatus 10′, the image pickup device 56 is provided inside the housing 50 and on the rear side of the barrel 52, and a space is provided in the housing 50 between a rear end of the barrel 52 and the image pickup device 56.